This article discusses variables definable by the maintainer in a PKGBUILD. For information on the PKGBUILD functions and creating packages in general, refer to Creating packages. Also read PKGBUILD(5).

A PKGBUILD is a shell script containing the build information required by Arch Linux packages.

Packages in Arch Linux are built using the makepkg utility. When makepkg is run, it searches for a PKGBUILD file in the current directory and follows the instructions therein to either compile or otherwise acquire the files to build a package archive (pkgname.pkg.tar.xz). The resulting package contains binary files and installation instructions, readily installable with pacman.

Mandatory variables are pkgname, pkgver, pkgrel, and arch. license is not strictly necessary to build a package, but is recommended for any PKGBUILDs shared with others, as makepkg will produce a warning if not present.

It is a common practice to define the variables in the PKGBUILD in same order as given here. However, this is not mandatory, as long as correct Bash syntax is used.

Package name

pkgbase

An optional global directive is available when building a split package. pkgbase is used to refer to the group of packages in the output of makepkg and in the naming of source-only tarballs. If not specified, the first element in the pkgname array is used. The variable is not allowed to begin with a hyphen. All values for split packages default to the global ones given in the PKGBUILD. Everything, except #makedepends, #Sources, and #Integrity variables can be overridden within each split package's package() function.

pkgname

The name(s) of the package(s). Package names should only consist of lowercase alphanumerics and the following characters: @._+- (at symbol, dot, underscore, plus, hyphen). Names are not allowed to start with hyphens or dots. For the sake of consistency, pkgname should match the name of the source tarball of the software: for instance, if the software is in foobar-2.5.tar.gz, use pkgname=foobar. The name of the directory containing the PKGBUILD should also match the pkgname.

Split packages should be defined as an array, e.g. pkgname=('foo' 'bar').

Version

pkgver

The version of the package. This should be the same as the version released by the author of the package. It can contain letters, numbers, periods and underscores, but not a hyphen (-). If the author of the software uses one, replace it with an underscore (_). If the pkgver variable is used later in the PKGBUILD, then the underscore can easily be substituted for a hyphen, e.g. source=("$pkgname-${pkgver//_/-}.tar.gz").

Note: If upstream uses a timestamp versioning such as 30102014, ensure to use the reversed date, i.e. 20141030 (ISO 8601 format). Otherwise it will not appear as a newer version.

Tip:

The ordering of uncommon values can be tested with vercmp(8), which is provided by the pacman package.

pkgrel

The release number. This is usually a positive integer number that allows to differentiate between consecutive builds of the same version of a package. As fixes and additional features are added to the PKGBUILD that influence the resulting package, the pkgrel should be incremented by 1. When a new version of the software is released, this value must be reset to 1. In exceptional cases other formats can be found in use, such as major.minor.

epoch

Warning:epoch should only be used when absolutely required to do so.

Used to force the package to be seen as newer than any previous version with a lower epoch. This value is required to be a positive integer; the default is 0. It is used when the version numbering scheme of a package changes (or is alphanumeric), breaking normal version comparison logic. For example:

Generic

pkgdesc

The description of the package. This is recommended to be 80 characters or less and should not include the package name in a self-referencing way, unless the application name differs from the package name. For example, use pkgdesc="Text editor for X11" instead of pkgdesc="Nedit is a text editor for X11".

Also it is important to use keywords wisely to increase the chances of appearing in relevant search queries.

arch

An array of architectures that the PKGBUILD is intended to build and work on. Arch officially supports only x86_64, but other projects may support other architectures. For example, Arch Linux 32 provides support for i686 and Arch Linux ARM provides support for arm (armv5), armv6h (armv6 hardfloat), armv7h (armv7 hardfloat), and aarch64 (armv8 64bit).

If a package is architecture-independent in its compiled state (shell scripts, fonts, themes, many types of extensions, etc.) then use arch=('any'). Please note that, as this is intended for packages that can be built once and used on any architecture, it will cause the package to be labeled -any as opposed to -x86_64, etc.

If instead a package can be compiled for any architecture, but is architecture-specific once compiled, specify all architectures officially supported by Arch, i.e. arch=('x86_64').

The target architecture can be accessed with the variable $CARCH during a build.

url

The URL of the official site of the software being packaged.

license

The license under which the software is distributed. The licenses package contains many commonly used licenses, which are installed under /usr/share/licenses/common/. If a package is licensed under one of these licenses, the value should be set to the directory name, e.g. license=('GPL'). If the appropriate license is not included, several things must be done:

Add custom to the license array. Optionally, you can replace custom with custom:name of license. Once a license is used in two or more packages in an official repository (including community), it becomes a part of the licenses package.

Install the license in: /usr/share/licenses/pkgname/, e.g. /usr/share/licenses/foobar/LICENSE. One good way to do this is by using:

install -Dm644 LICENSE "$pkgdir/usr/share/licenses/$pkgname/LICENSE"

If the license is only found in a website, then you need to separately include it in the package.

The BSD, MIT, zlib/png and Python licenses are special cases and could not be included in the licenses package. For the sake of the license array, it is treated as a common license (license=('BSD'), license=('MIT'), license=('ZLIB') and license=('Python')), but technically each one is a custom license, because each one has its own copyright line. Any packages licensed under these four should have its own unique license stored in /usr/share/licenses/pkgname.

Some packages may not be covered by a single license. In these cases, multiple entries may be made in the license array, e.g. license=('GPL' 'custom:name of license').

(L)GPL has many versions and permutations of those versions. For (L)GPL software, the convention is:

(L)GPL — (L)GPLv2 or any later version

(L)GPL2 — (L)GPL2 only

(L)GPL3 — (L)GPL3 or any later version

If after researching the issue no license can be determined, PKGBUILD.proto suggests using unknown. However, upstream should be contacted about the conditions under which the software is (and is not) available.

Tip: Some software authors do not provide separate license file and describe distribution rules in section of common ReadMe.txt. This information can be extracted to a separate file during build() with something like sed -n '/This software/,/ thereof./p' ReadMe.txt > LICENSE

Additional information and perspectives on free and open source software licenses may be found on the following pages:

groups

The group the package belongs in. For instance, when installing the kdebase package, it installs all packages belonging in that group.

Dependencies

Note: Additional architecture-specific arrays can be added by appending an underscore and the architecture name, e.g. optdepends_x86_64=().

depends

An array of packages that must be installed before the software can be run. Version restrictions can be specified with comparison operators, e.g. depends=('foobar>=1.8.0'); if multiple restrictions are needed, the dependency can be repeated for each, e.g. depends=('foobar>=1.8.0' 'foobar<2.0.0').

Dependencies that are provided by other dependencies do not need to be listed. For instance, if a package foo depends on both bar and baz, and the bar package depends in turn on baz too, baz does not need to be included in foo's depends array.

If the dependency name appears to be a library, e.g. depends=('libfoobar.so'), makepkg will try to find a binary that depends on the library in the built package and append the version needed by the binary. Appending the version yourself disables automatic detection, e.g. depends=('libfoobar.so=2').

optdepends

An array of packages that are not needed for the software to function, but provide additional features. This may imply that not all executables provided by a package will function without the respective optdepends.[1] If the software works on multiple alternative dependencies, all of them can be listed here, instead of the depends array.

A short description of the extra functionality each optdepend provides should also be noted:

makedepends

An array of packages that are only required to build the software. The minimum dependency version can be specified in the same format as in the depends array. The packages in the depends array are implicitly required to build the package, they should not be duplicated here.

Tip: The following can be used to check whether a particular package is either in the base-devel group or is pulled in by a member of the group:

Note: The group base-devel is assumed to be already installed when building with makepkg. Members of this group should not be included in makedepends array.

checkdepends

An array of packages that the software depends on to run its test suite, but are not needed at runtime. Packages in this list follow the same format as depends. These dependencies are only considered when the check() function is present and is to be run by makepkg.

Note: The group base-devel is assumed to be already installed when building with makepkg. Members of this group should not be included in checkdepends array.

Package relations

Note: Additional architecture-specific arrays can be added by appending an underscore and the architecture name, e.g. conflicts_x86_64=().

provides

An array of additional packages that the software provides the features of (or a virtual package such as cron or sh). Packages providing the same item can be installed side-by-side, unless at least one of them uses a conflicts array.

Note: The version that the package provides should be mentioned (pkgver and potentially the pkgrel), in case packages referencing the software require one. For instance, a modified qt package version 3.3.8, named qt-foobar, should use provides=('qt=3.3.8'); omitting the version number would cause the dependencies that require a specific version of qt to fail. Do not add pkgname to the provides array, as it is done automatically.

conflicts

An array of packages that conflict with, or cause problems with the package, if installed. All these packages and packages providing this item will need to be removed. The version properties of the conflicting packages can also be specified in the same format as the depends array.

This means when you write a package for which an alternate version is available (be it in the official repositories or in the AUR) and your package conflicts that version, you need to put the other versions in your conflicts array as well.

However, there is an exception to this rule. Defining conflicting packages in all directions is not always applicable especially if all these packages are maintained by different people. Indeed, having to contact all package maintainers of packages conflicting with your own version and ask them to include your package name in their conflicts array is a cumbersome process.

This is why, in this context, if your package provides a feature and another package provides the same feature, you do not need to specify that conflicting package in your conflicts array. Let us take a concrete example:

netbeans-phpAUR provides netbeans and conflicts with netbeans but does not need to conflicts with netbeans-javaseAUR since pacman is smart enough to figure out these packages are incompatible as they provide the same feature and are in conflict with it.

The same applies in the reverse order: netbeans-javaseAUR does not need to conflict with netbeans-phpAUR, because they provide the same feature.

replaces

An array of obsolete packages that are replaced by the package, e.g. wireshark-gtk uses replaces=('wireshark'). When syncing, pacman will immediately replace an installed package upon encountering another package with the matching replaces in the repositories. If providing an alternate version of an already existing package or uploading to the AUR, use the conflicts and provides arrays, which are only evaluated when actually installing the conflicting package.

Others

backup

An array of files that can contain user-made changes and should be preserved during upgrade or removal of a package, primarily intended for configuration files in /etc.

Files in this array should use relative paths without the leading slash (/) (e.g. etc/pacman.conf, instead of /etc/pacman.conf).

When updating, new versions may be saved as file.pacnew to avoid overwriting a file which already exists and was previously modified by the user. Similarly, when the package is removed, user-modified files will be preserved as file.pacsave unless the package was removed with the pacman -Rn command.

install

The name of the .install script to be included in the package. This should be the same as pkgname. pacman has the ability to store and execute a package-specific script when it installs, removes or upgrades a package. The script contains the following functions which run at different times:

pre_install — The script is run right before files are extracted. One argument is passed: new package version.

post_install — The script is run right after files are extracted. One argument is passed: new package version.

pre_upgrade — The script is run right before files are extracted. Two arguments are passed in the following order: new package version, old package version.

post_upgrade — The script is run right after files are extracted. Two arguments are passed in the following order: new package version, old package version.

pre_remove — The script is run right before files are removed. One argument is passed: old package version.

post_remove — The script is run right after files are removed. One argument is passed: old package version.

Note: Do not end the script with exit. This would prevent the contained functions from executing.

changelog

The name of the package changelog. To view changelogs for installed packages (that have this file):

$ pacman -Qc pkgname

Sources

source

An array of files needed to build the package. It must contain the location of the software source, which in most cases is a full HTTP or FTP URL. The previously set variables pkgname and pkgver can be used effectively here; e.g. source=("https://example.com/$pkgname-$pkgver.tar.gz").

Files can also be supplied in the same directory where the PKGBUILD is located, and their names added to this array. Before the actual build process starts, all the files referenced in this array will be downloaded or checked for existence, and makepkg will not proceed if any is missing.

.install files are recognized automatically by makepkg and should not be included in the source array. Files in the source array with extensions .sig, .sign, or .asc are recognized by makepkg as PGP signatures and will be automatically used to verify the integrity of the corresponding source file.

Warning: The downloaded source filename must be unique because the SRCDEST directory can be the same for all packages. For instance, using the version number of the project as a filename potentially conflicts with other projects with the same version number. In this case, the alternative unique filename to be used is provided with the syntax source=('unique_package_name::file_uri'); e.g. source=("$pkgname-$pkgver.tar.gz::https://github.com/coder/program/archive/v$pkgver.tar.gz").

Tip:

Additional architecture-specific arrays can be added by appending an underscore and the architecture name, e.g. source_x86_64=(). There must be a corresponding integrity array with checksums, e.g. sha256sums_x86_64=().

Some servers restrict download by filtering the User-Agent string of the client, this can be circumvented with DLAGENTS.

noextract

An array of files listed under source, which should not be extracted from their archive format by makepkg. This can be used with archives that cannot be handled by /usr/bin/bsdtar or those that need to be installed as-is. If an alternative unarchiving tool is used (e.g. lrzip), it should be added in the makedepends array and the first line of the prepare() function should extract the source archive manually; for example:

prepare() {
lrzip -d source.tar.lrz
}

Note that while the source array accepts URLs, noextract is just the file name portion:

If source contains only plain URLs without custom file names, strip the source array before the last slash:

noextract=("${source[@]##*/}")

If source contains only entries with custom file names, strip the source array after the :: separator (taken from firefox-i18n's PKGBUILD):

noextract=("${source[@]%%::*}")

validpgpkeys

An array of PGP fingerprints. If used, makepkg will only accept signatures from the keys listed here and will ignore the trust values from the keyring. If the source file was signed with a subkey, makepkg will still use the primary key for comparison.

Only full fingerprints are accepted. They must be uppercase and must not contain whitespace characters.

Note: You can use gpg --list-keys --fingerprint <KEYID> to find out the fingerprint of the appropriate key.

Integrity

These variables are arrays whose items are checksum strings that will be used to verify the integrity of the respective files in the source array. You can also insert SKIP for a particular file, and its checksum will not be tested.

The checksum type and values should always be those provided by upstream, such as in release announcements. When multiple types are available, the strongest checksum is to be preferred: sha256 over sha1, and sha1 over md5. This best ensures the integrity of the downloaded files, from upstream's announcement to package building.

Note: Additionally, when upstream makes digital signatures available, the signature files should be added to the source array and the PGP key fingerprint to the validpgpkeys array. This allows authentication of the files at build time.

The values for these variables can be auto-generated by makepkg's -g/--geninteg option, then commonly appended with makepkg -g >> PKGBUILD. The updpkgsums command is able to update the variables wherever they are in the PKGBUILD. Both tools will use the variable that is already set in the PKGBUILD, or fall back to md5sums if none is set.

The file integrity checks to use can be set up with the INTEGRITY_CHECK option in /etc/makepkg.conf. See makepkg.conf(5).

Note: Additional architecture-specific arrays can be added by appending an underscore and the architecture name, e.g. sha256sums_x86_64=().

md5sums

An array of 128-bit MD5 checksums of the files listed in the source array.

sha1sums

An array of 160-bit SHA-1 checksums of the files listed in the source array.